Everything you need to know about flat roofs and wood fibre.

In this episode of the ‘Can I Just Ask?’ series; Chris and Andy take on flat roofs, the most moisture sensitive roof construction there is, and the three ways we specify them with wood fibre. The ventilated build is the most robust but the deepest. The unventilated build is the slimmest and simplest to detail, though it relies on solar drying and rules out green roofs, solar panels and shaded sites. The hybrid swaps the wood fibre sarking for XPS to buy back that versatility, at a cost in embodied energy, thermal mass and decrement delay. Whichever you choose, the roof covering is still what determines whether it lasts.